1. Field of the Invention
The present invention relates to a thermal transfer printer, and more particularly to a thermal transfer printer of a type reserving ribbon cassettes at a plurality of predetermined positions to select a required ribbon cassette from the plural ribbon cassettes to mount the selected ribbon cassette on a carriage so as to record data by using the selected ribbon cassette.
2. Description of the Prior Art
In recent years, there arises a desire for color printing, and a thermal transfer printer capable of forming a color image has been desired. An ink ribbon 80 for use in a general color thermal transfer printer has a structure such that three color ink portions consisting of yellow (Y), magenta (M) and cyan (C) color ink portions or four color ink portions consisting of the foregoing three color ink portions and a black (B) color portion are repeatedly formed in a lengthwise direction of the ink ribbon 80 in such a manner that each color ink portion is longer than a width to be printed. In accordance with data to be recorded, each color ink portion is selected to perform recording.
In a thermal transfer printer of a type using an ink ribbon of the foregoing type, a color portion, which is not used in the present recording operation, is skipped and a next color ink portion is selected to perform recording. If a portion, which is not recorded, exists in the same line, the ink ribbon is inevitably moved. Therefore, portions, which are not used in the recording operation, are wasted, thereby enlarging the running cost. Moreover, the amount of ribbon cassettes to be used is enlarged, thus causing an environmental problem to arise in that garbage of used cassette increases.
To overcome the foregoing problems, the applicant of the present invention has disclosed a thermal transfer printer for performing a color recording operation by changing ribbon cassettes in such a manner that ribbon cassettes each accommodating a monotone ink ribbon are held in a plurality of portions, a ribbon cassette accommodating an ink ribbon for the color for use in the recording operation is selected, and the selected ribbon cassette is mounted on a carriage to perform recording (refer to, for example, Japanese Patent Laid-Open No. 2103173 and Japanese Patent Laid-Open No. 2-103174).
Since only a portion of the ink ribbon, which is used in the recording operation, is fed in the thermal transfer printer for color recording of a type changing the ribbon cassette, the ink ribbon can substantially fully be used in the recording operation. Thus, the running cost and the amount of ribbon cassettes to be disposed can be reduced as compared with the foregoing thermal transfer printer of the type using the repetitive type ink ribbon.
With a thermal transfer printers of the type changing the ribbon cassette disclosed in Japanese Patent Laid-Open No. 2-103173 or Japanese Patent Laid-Open No. 2-103174, ink ribbons to be mounted on the corresponding cassette holding portions are previously determined. Thus, if a ribbon cassette accommodating a different color ink ribbon is mounted, a desired result cannot be realized in printing. Moreover, in a case where color printing is not required, lowering of the frequency of change of the ribbon cassette in such a manner that a plurality of the same color ribbon cassettes are prepared cannot be lowered.